1. Field of the Invention
The present invention relates-to an apparatus for transporting parts, and particularly relates to an apparatus for transporting parts which separates the first part in a row of parts being transported from the second part in this row.
2. Description of the Related Art
Regarding apparatuses for transporting small parts such as chip parts, an apparatus is known wherein an endless belt comprises the bottom of a transporting groove through which parts are guided, and wherein the parts are transported by means of intermittent driving of this belt (see Japanese Unexamined Patent Publication No. 8-48419). In the case of this apparatus, a mechanism is provided for separating the first part in the row on the belt from the second part in the row, so as to allow the first part in the row to be extracted therefrom. This separating mechanism acts so that a stopper is brought into contact with the front-most end of a guiding groove at the time that the parts on the belt move forward with the forward motion of the belt, the first part is stopped at a certain position, and upon the first part coming into contact with the stopper so that motion of all parts is stopped, the second part is held in the same position by a holding pin while the stopper is opened forwards so as to allow the first part to proceed forward while remaining in the state of being attached by a permanent magnet on the stopper, thereby forcibly forming a gap between the first part and the second part.
However, this method in the above separating mechanism involves stopping the movement of all parts, attaching the first part by a permanent magnet provided in the stopper, and pulling this part forward by magnetic force, meaning that the parts cannot be separated in the event that the part is formed of a non-magnetic material, or that debris or the like is on the part such that magnetism does not effectively work. Also, friction occurs between the part and belt at the time of extracting the first part, so there is the possibility that the attachment between the permanent magnet and the part may be separated. Thus, such an arrangement has the problem of being unreliable.
Also, with the above separating mechanism, the space above the first part is opened at the time of using magnetism to attach the first part and move the stopper forwards, so trouble such as the first part flying off of the belt may occur. Such trouble tends to occur particularly when transporting and separating small parts at high speeds. Accordingly, parts cannot be extracted in a stable manner.
Accordingly, it is an object of the present invention to provide an apparatus for transporting parts, wherein the first part and second part can be separated in a sure manner even in the event that the parts are non-magnetic material, and wherein ease of extracting of the first part is facilitated, in a stable manner.
In order to achieve the above objects, a part transporting apparatus according to a first aspect of the present invention comprises: a guiding groove for lining up parts in one row and guiding the parts; a transporting member which is provided at the base of the guiding groove and transports parts in one direction by itself moving forwards and backwards along the groove; a driving means for reciprocally driving the transporting member in the forward and backward directions; a shutter covering the space over the first part, the shutter being capable of being opened and closed over the tip of the guiding groove; a stopper which operates so as to open and close in the width direction of the guiding groove, and hold the second part from the front of the row of parts being transported on the upper plane of the transporting member; and a synchronizing means for opening and closing the stopper synchronously with the reciprocal forward and backward movement of the transporting member; wherein, once the stopper holds the second part, the transporting member moves forward by a certain distance, thereby separating the first part in the row and the second part, and immediately before the forward movement of the transporting member is completed, the shutter is opened in a manner synchronous with the transporting member.
The first characteristic of the present invention is that the transporting member is reciprocally driven in the forward and backward directions to transport the parts forward, and that once the stopper holds the second part, the transporting member moves further forward, thereby separating the first part and the second part. Accordingly, the driving mechanism is simplified in comparison with known intermittent driving mechanisms using belts, and the first part and second part can be separated in a sure manner even in the event that the part is non-magnetic.
The second characteristic of the present invention is that a shutter covering the space over the first part is provided to the tip of the guiding groove, wherein the shutter is opened in a manner synchronous with the transporting member immediately before the forward movement of the transporting member is completed, so that the first part can be extracted from the guiding groove. In other words, preventing the first part from flying out of the guiding groove at the time of separating the first part and second part enables stable extracting.
In order to prevent the first part from flying out in a sure manner during transporting and separating thereof, it is preferable to keep the space above the part covered with the cover until immediately before extracting. To this end, according to a third aspect of the present invention, the shutter comprises: a cover covering the space over the first part; and a rotating shaft for axially supporting the shutter so as to be rotatable in the forward and backward directions; wherein the transporting member is capable of coming into contact with an intermediate portion between the rotating shaft of the shutter and the cover, so that the shutter is pressed forwards by the transporting member, and the cover of the shutter opens forward at a speed greater than the speed of forward progression of the transporting member. That is, pressing the shutter with the transporting material near the fulcrum of rotation allows the shutter to be opened with minimal movement of the transporting member.
Regarding the method of transporting the parts in one direction with the transporting member, it is preferable that friction is used, according to a second aspect of the invention. That is, the driving means drives the transporting member in a reciprocal manner such that the speed of moving in the backward direction is greater than the speed of moving in the forward direction; wherein the speed of moving in the forward direction is a speed at which holding friction acts between the transporting member and the parts disposed upon the upper surface thereof; and wherein the speed of moving in the backward direction is a speed at which the friction between the transporting member and the parts disposed upon the upper surface thereof is essentially broken. With such an arrangement, the parts can be transported in one direction simply by reciprocal driving of the transporting member, so the transporting mechanism can be simplified, and further, the parts are not restrained, so there is little damage inflicted upon the parts. Incidentally, the term xe2x80x9cthe friction . . . is essentially brokenxe2x80x9d includes not only speeds at which friction does not act at all, but also speeds at which the parts do not actually move backwards even if friction does act.